#tupian { 
background-image: url(../images/1.jpg);
width:500px;
height:750px;
transform:rotate(45deg);/*旋转45度 */
box-shadow:1px 1px 4px rgba(0,0,0,.25);  /*阴影 透明度25*/
}

body {
    background-color: lightblue;
} 
#aaa{
    background-color: lightblue;
}